Fluid pressure brake equipment



E. E. HEWITT FLUID PRESSURE BRAKE EQUIPMENT March 23, 1937.

Filed Aug. 25, 1954 2 Sheets-Sheet 1 QM Qm INVENTOR ELLIS EHEIWITT JM ATTORNEY March 23, 1937. E E, HEWlTT 2,074,747

FLUID PRESURE BRAKE EQUIPMENT Filed Aug. 25, 1934 2 Shee'cs-Sheei'I 2 mvENToR ELLIS E. HEWITT n BY 0%/4/ ATTORNE v latented Mar. 23, 1937 v UNITED STATES PATENT OFFICE FLUIDy PRESSURE BRAKE EQIUPIWENT Ellis E. Hewitt, Edgewood, Pa., assignor to The Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of Pennsylvania Application August 23, 1934, Serial No. '741,064

21 Claims. (Cl. 303-24) My invention relates to braking equipment and Figs. 1 and 2, taken together, comprise a diamore particularly to such equipment for use on grammatic view, mainly in section, showing cirhigh speed multiple unit cars and railway trains. cuits and apparatus illustrating one preferred In trains and traction vehicles designed for embodiment of the invention; high speed service, it is essential that a braking Fig. 3 is a diagrammatic View of the pneumatic equipment be provided that combines a high brake valve; and degree of reliability and safety with simplicity Fig. 4 is a plan view taken partly in section of operation. along the line 4 4 in Fig. 1.

In accordance with my invention, an electro- Referring to the drawings, and more particm pneumatic brake equipment is provided includularly to Figs. 1 and 2 thereof, each car or train 10 ing an electric self-lapping brake valve having a unit may be provided with braking equipment,

self-lapping device controlled by straight air presincluding a brake cylinder I and a control valve sure, and that controls magnet valve devices of assembly 2 that is controlled, either electrically a control valve assembly for controlling the or pneumatically, in accordance with the opera- ]3 application and release of the brakes. A retion of a brake valve device 3, having an electric 15 tardation controller in the form of an inertia reself-lapping control portion for controlling the sponsive device is provided for also controlling supply of fluid under pressure from a main reserthe magnet valve devices to limit the degree of Voir 4 to the brake cylinder I through a main application of the brakes in a manner to prevent reservoir pipe 5 and from the brake cylinder I g() the rate of deceleration of the vehicle from exto the atmosphere. A retardation controller 6 ceeding a predetermined value. is provided for limiting the degree of application A brake equipment of the same general charof the brakes when effected by electrical control acter as outlined above is disclosed and claimed of the control valve assembly. Pneumatic control in my copending United States patent applieaof the control valve assembly 2 effects the apgr, tion, Serial No. 717,213, led March 24, 1934, plication and release of the brakes in accordance 2- relating to Braking apparatus and assigned to with the operation of a valve associated with the same assignee as this application. In my the brake valve device 3 to produce variations in above referred to copending application, one pair uid pressure within the usual brake pipe l. of magnet valve devices is provided on the con- The brake valve device 3 may comprise an elec- 39 trol valve assembly to be controlled by the sel'ftric self-lapping portion for controlling normal lapping valve device and another pair of magservice applications of the brakes, and a rotary net valve devices is provided to be controlled valve portion for controlling auxiliary service by the retardation controller. In the invention and regular emergency applications, and is prodisclosed in this application a single pair of vided with a casing 8 defining a chamber 9,

35 magnet valve devices is provided on each control through one end of which an operating shaft 3- valve assembly, and are controlled both by the II extends that is provided at its upper end with self-lapping brake valve device and by the rea brake valve handle I2.

tardation controller. Other improvements in the A cam I3 for controlling the electric self-lapapparatus described will appear from the folping portion, is carried by the shaft II. The 40 lowing specication. upper face of the cam engages the rounded end 40 It is an object of my invention to provide an I4 of a floating operating lever I5 that is urged equipment of the above indicated character that downwardly against the face of the cam by a is particularly adapted for high speed train and spring I6 that is `positioned between the upper vehicle service and in which the application and wall of the brake valve casing structure and the 45 release of the brakes may be effected by elecend I4 of the lever I5. The other end of the tropneumatic straight air operation, or by autooating lever I5 is pivotally connected by a pin matic operation. 20 to a link I1 that is pivotally connected by a Another object of my invention is the provipin I8 to a contact carrying lever I9 that sup-V sion of equipment in which the brakes are autoports and carries movable contact members 2| ,50 matically maintained applied to provide a deand 22 that are electrically connected together by 50 sired rate of retardation of the vehicle. a conductor 23.

Other objects and advantages of my invention The movable Contact member 2l iS adapted ISO will be apparent from the following description engage the fixed contact member 24 that is when taken in connection with the accompanyconnected to the trainwire 25, and the movable 55` ing drawings; in which contact member 22 is adapted to engage the fixed 55 Contact member 26 that is connected by conductor 21 to one terminal of a source of current such as the battery 28 and to also engage a contact member 29 that is connected to the train wire 3|. The contact carrying lever I9 is urged upwardly by a spring 32, the lower end of which is inserted in a recess in the casing structure, and lthe upper end of which engages the lever I9 and presses it upwardly until the left end thereof engages the under side of a stop 33 and the contact members 2| and 22 are moved out of engagement with the contact members 24 and 26 and 29, respectively, unless and until the contact carrying lever I9 is urged downwardly by operation of the iloating lever I5.

The floating lever I5 is pivoted at a point intermediate its end on a pin 34 that is supported in a stem 35 that extends upwardly from a self-lapping piston 36 contained in the piston chamber 31. A spring 38 positioned about the stem 35, having its lower end in engagement with the self-lapping piston 36 and its upper end in engagement with a nut 39, urges the piston 36 downwardly to its illustrated position. The relative forces exerted by the springs 38 and 32 are such that when the left hand end I4 of the lever I5 is in its lower or illustrated position, the spring 32 exerts a sufficient upward force on the contact carrying lever I9 and the link I1 to effect a separation of the movable contact members 2| and 22 from their associated stationary contact members.

The rotary valve 4|, contained within a valve chamber 42, is provided with a port 45 adapted to register with a passage leading to the brake pipe 1 when the valve is positioned in the electrical application and pneumatic release Zone, so that fluid at the reduced pressure as supplied through the reducing feed valve device 43 from the main reservoir to the rotary valve chamber 42 is supplied through port 45 to the brake pipe 1.

In pneumatic service position, the brake pipe 1 is connected to the atmosphere exhaust port 46 through a cavity 41 in the rotary valve 4|, and in pneumatic emergency position, the brake pipe is connected to the exhaust port 46 through a cavity 48,

The straight air pipe 40 communicates with the piston chamber 31 of the self-lapping piston 36 and also with the piston chambers of the relay valve devices associated with each control valve assembly 2 for a purpose to be later explained.

The retardation controller 6 comprises an inertia device, such as a pendulum 49, contained Within a casing 50 and pivotally supported thereto by a pivot pin 69. The pendulum 49 is adapted, upon a predetermined movement toward the left, to operatively engage a switch contact member 5| and actuate it out of engagement with the switch contact member 52 to interrupt a circuit connection between a conductor 25 and a conductor 53, and upon a further predetermined movement toward the left, to operatively engage a switch contact member 54 and actuate it out of engagement with a switch contact member 55 to interrupt a circuit connection between a conductor 3| and a conductor 56. In a similar manner the pendulum 49 is adapted, upon a predetermined movement toward the right, to operatively engage a switch contact member 51 that normally engages the switch Contact member 58, and separate it therefrom, thus interrupting a circuit connection between the conductor 53 and a train wire conductor 59, and upon a further predetermined movement toward the right, to operatively engage the switch contact member 6| that normally is in engagement with a switch contact member 62, and move the switch member 6| from engagement with the contact member 62, to interrupt a circuit connection between the conductor 56 and a train wire conductor 63.

The pendulum 49 is engaged by spring pressed plungers 64 and 65 that resist its movement from a vertical position. The plunger 64 is provided with a central bore for accommodating a spring 66, one end of which is in engagement with the lower end of the bore, and the other end of which engages an adjusting nut 61, that is screwthreadedly attached within the bore of a stop member 68 that is attached within the outer end of a sleeve 69, the lower end of which surrounds and supports the plunger 64. The plunger 64 is provided at its outer end with an outwardly extending ange 1I that engages a shoulder on the sleeve 69 to limit the movement of the plunger toward the pendulum. The lower end of the sleeve 69 is provided with an outwardly extending flange 12 that engages a portion of the controller casing to limit its inward movement and to accommodate a spring 13 that is positioned about the sleeve. The lower end of the spring engages the outwardly extending flange 12 and the upper end is contained within a portion of a sleeve 14, attached to the controller casing, and engages an inwardly extending shoulder therein.

Upon some predetermined rate of deceleration of the vehicle, assuming movement of the vehicle to be toward the left as viewed in Fig. l, the inertia of the pendulum 69 will be sufficient to move it, and the plunger 64, toward the left against the bias of the spring 66, until the ilange 'II engages the stop 68 and the switch contact member 5| is separated from engagement with the switch contact member 52. The force of the spring 13 is suilcient to maintain the sleeve 69 in its illustrated position, in which the sleeve iange 12 is maintained in engagement with the controller casing. Upon a predetermined greater rate in the deceleration of the vehicle, the inertia of the pendulum 49 will force the plunger 64 further toward the left causing the stop 68 and the sleeve 69 to move against the bias of the spring 13 until the switch Contact member 54 has been separated from the switch contact member 55 to interrupt the circuit connection between the conductors 3| and 56. The parts associated with the spring pressed plunger 65 are identical in construction and operation to those associated f' with the spring pressed plunger 64 and are, therefore, not described in detail.

The control valve assembly 2 comprises a pipe bracket section 8|, a relay valve section 82, a triple valve section 83, an inshot valve section 84, and a magnet valve section 65. The magnet valve section 65 comprises a release magnet valve device 86 and an application magnet valve device 81. The release magnet valve device comprises a magnet 88, operatively connected to a release valve 89, for controlling communication between the release valve chamber 9| and a chamber 90. The release valve chamber 9| is normally connected to the atmosphere through passage 92, cavity 93 in the slide valve |45 of the triple valve device, and atmospheric exhaust passage 94. The straight air pipe 48 is connected to the application piston chamber 91 in the relay valve device and through a restricted port 95 to the chamber 90. A spring 98 is provided in the chamber 90 for biasing the release valve 89 to its unseated position.

The application magnet valve device 81 comprises a magnet IDI, operatively connected to an application valve |02. The application valve |02 controls communication from the auxiliary reservoir |06, which is connected through passage |05 with chamber |64 to chamber |03, which is connected through passage 96 with the straight air pipe 40, so that when the valve |52 is unseated, fluid under pressure is supplied from the auxiliary reservoir to the straight air pipe. A spring |08 is provided in the application magnet valve chamber for urging the valve |02 to its seat.

The relay valve section 52 comprises a casing having the piston chamber 91 containing an application piston |08 which is adapted, through the medium of a stem |05, to operate a slide valve l, that is operatively connected to the stem and contained in a valve chamber H2 that is in constantly open communication with' the brake cylinder through passage and pipe II3. 'I'he slide valve controls communication between the valve chamber H2 and the atmosphere through ports ||4 and I5 and the exhaust passage I6.

Also contained within the relay valve section is a supply valve ||1 slidably mounted within the cylindrical wall H0 carried by a partition wall H6, and provided with a stern |20 adapted to be engaged by the end of the piston stem |05. The supply valve ||1 is subject to the pressure of a spring I2| and to the fluid pressure within a pilot valve chamber |22, that is separated from the supply valve chamber |23 by the partition wall M0, and that is in communication therewith through a restricted port |24. The supply valve chamber |23,` is in constantly open communication with the main reservoir pipe 5 through passage and pipe |25, a volume reservoir |25 being interposed in the pipe |25. A pilot valve |21 is provided within the supply valve for controlling communication between the pilot valve chamber |22 and the slide valve chamber ||2, and is provided with a pilot valve stern |25 extending through the hollow supply valve stem |20 and beyond the face thereof and which is adapted to be engaged by the end of the piston stem |00 prior to the engagement of the stem |00 with the supply valve stem 20.

The relay valve device is shown in its brake release position, in which position the application piston |08 and the slide valve ||i are in their extreme lower or brake releasing positions. When the slide valve III is in this position, the valve chamber ||2 and consequently the brake cylinder i, are in communication with the atmosphere through an exhaust passage |6. With the application piston |58 in its release position, the stem |60 will be out of engagement with the end of the supply valve stem |20 andthe pressure of the spring |2| will maintain the supply valve seated against its ring seat |3I, thereby maintaining communication closed from the supply valve chamber |23, that is constantly connected to the main reservoir pipe 5, to the slide valve chamber H2. In this position oi' the application piston, the stem |09 will likewise be out of engagement with the end of the pilot valve stem |29, so that the pressure of the spring |28 will maintain the pilot valve |21 seated, thereby maintaining communication closed from the pilot valve chamber |22 to the slide valve chamber A baille piston |32 is provided on the stem |03 A and defines a chamber |33, at the upper side of the application piston |08, that is in communication with the slide valve chamber II2 through a restricted port |54 and the passage 3. The baille piston prevents changes in pressure within the valve chamber |2 from being too rapidly communicated to the upper side of the application piston |08, which, under some conditions, might cause a pumping action of the relay valve. In the release position of the application piston |65, the chamber |33 is also connected to the atmosphere through a passage |35 extending through the casing of the relay valve device.

The triple valve section 03 comprises a casing having a piston chamber I4I, that is in constant communication, through passage and pipe |42, with the brake pipe 1, and that contains a piston |43 provided with a stem |44 that operatively engages a slide valve |45 and a graduating valve |46, contained within the slide valve chamber |01 that is in constant communication through passage and pipe |05 with the auxiliary reservoir |06. A brake cylinder volume reservoir |41 is provided and is connected to a pipe and passage |48 that terminates in the seat of the slide valve |45. ln the illustrated, or release, position of the triple valve piston |43 and slide valve |45, the cavity 9.3 in the slide valve registers with the exhaust passage 95 and with the passages 92 and |48 that communicate, respectively, with the release valve chamber 9| and with the brake cylinder volume reservoir |41, thus connecting these two chambers with the atmosphere.

A check valve I5| is also provided within the casing of the triple valve section for controlling communication between a chamber |52, that is in constant communication with the passage |42, and a check valve chamber |53. In the release position of the piston |45, the chamber |53 is in communication with the valve chamber |01', through a passage |54 leading to the slide valve seat, and port |55 in the slide valve |45. The check valve |5| is provided with` a stem |56v that is slidably mounted in a bore in a cap nut |51, that is screw-threadedly attached to the casing of the triple valve section. The check valve I5I is subject to the pressure of a spring |58 that urges the valve to its ring seat |59, to prevent flow of uid under pressure from the slide valve chamber |0'i to the brake pipe 1 while permitting the valve chamber |61 and theV auxiliary reservoir |06 to be charged from the brake pipe past the valve |5I independently of the charging that occurs through the feed groove |1I past the piston |43.

The pressure limiting valve section 84 includes a pressure limiting valve device 6| having a casing containing a valve chamber |62 that is connected to a passage which leads to the seat of the slide valve |45. A ball valve |63- is provided in the valve chamber |62 and is illustrated as held from its seat by a stem |64 that extends upwardly from a piston |65, that is slidably mounted Within the casing, and is provided with a stem |66 that extends downwardly through a bore in the cap nut |61. The piston |65 and the stem |64 are urged upwardly by a spring |60 to unseat the valve |63 and maintain communication between the passages |60 and 96, until the pressure within the valve chamber |62, and on the upper side of the piston I 65, increases suiliciently to urge the piston |65 downwardly against the pressure of the spring |68, thus permitting the valve |63v to seat. The pressure limiting valve device is elective to limit the pressure of uid supplied to the application chamber 9,1.

of the relay valve device through the triple valve device upon operation of the triple valve to its service or emergency position.

The pressure limiting valve section 84 of the control valve assembly also includes a safety valve device |69 to limit pressure in the piston chamber 91 to a predetermined value for which the safety valve is set to operate, when the slide valve |45 is in a position to close communication from the chamber 91 to the atmosphere through exhaust passage 94 and when the valve 89 is unseated. The safety valve device |69 is eiective, upon movement of the release valve 09 from its seated position while the slide valve |45 of the triple valve device is in other than its release position, to permit the ow of uid under pressure from the piston chamber 91 of the relay valve device until the pressure within this chamber has reached some predetermined low valueV at which the safety valve operates to close communication to the atmosphere.

During the initial charging of the system, the various parts of the apparatus remain in their release, or illustrated, positions, and fluid under pressure ows from the main reservoir 4, through the main reservoir pipe 5 to the volume reservoir |26 associated with each control valve assembly employed on the system, and through pipe and passage to the supply valve chamber |23 and the pilot valve chamber |22. With the rotary valve 4| in pneumatic release position, fluid under pressure supplied by the feed valve device 43 flows through passage 44 to the rotary valve chamber 42 of the brake valve device and through port 45 in the rotary valve to the brake pipe 1. Fluid under pressure supplied to the brake pipe 1, flows through pipe and passage |42, to the piston chamber |4| of each triple valve device.v From the piston chamber I4I, fluid under pressure ows past the piston |43, through the feed groove |1| to the slide valve chamber |01, and from this chamber through the passage and pipe |05 to charge the auxiliary reservoir |06, and through passage |05 to the application valve chamber |04. The initial charging of the slide valve chamber |01 will also take place partly through the passage |42, past the check valve I5I, through passages |54 and |55, so long as the pressure of fluid supplied to chamber |52 is sufeient to overcome the fluid pressure on the opposite side of the valve plus the pressure of the spring |58.

If the operator wishes to apply the brakes, the handle I2 of the brake valve device 3 is moved from its release position to a position within its electric application zone, depending upon the desired degree of application of the brakes. As the brake valve handle I2 is moved the cam I3 is rotated about its axis, thus raising the end I4 of' the iloating lever I5 which pivots about the pin 34, forcing the link I1 downwardly.

Upon downward movement of the connectingv link I1, and the pivot pin I 8, the contact carrying arm I9 pivots about the stop 33, the left end of the lever being held in engagement with the stop 33 by the spring 32, until the right hand end has moved downwardly suiiiciently to cause engagement of the contact member 22 with the contact members 26 and 29. This closes a circuit from the battery 28, through conductor 21, contact members 26, 22 and 29, conductor 3|, switch contact members 54 and 55, conductor 56, switch contact members 6| and 62, conductor 63, the winding of the electromagnet 88 of the releasemagnet valve device 8B to ground at I8I, to the grounded terminal |82 of the battery 28. The closing of the above traced circuit causes the release magnet valve 89 to be moved to close communication between the piston chamber 91 of the relay valve device and the atmosphere.

A further downward movement of the link I1 and pin I8 causes the contact carrying lever I9 to fulcrum about its right end, compressing the spring 32 and causing the contact member 2| to engage the contact member 24, thus closing a circuit from the battery 28 through conductor 21, contact members 26 and 22, conductor 23, contact members 2| and 24, conductor 25, switch contact members 5I and 52 on the retardation controller, conductor 53, switch contact members 51 and 58, conductor 59, the winding of the magnet |0I, to ground at I8I and to the grounded terminal |82 of the battery 28. Closing the above traced circuit causes the magnet |0| to be energized, so as to move the application valve |02 downwardly from its seat, opening communication from the Valve chamber |04, that is in open communication with the auxiliary reservoir |88 and with the slide valve chamber |01, to the piston chamber 91 through chamber 93 and passage 96. Fluid under pressure also flows from the passage 96 through the straight air pipe 43 to the self-lapping piston chamber 31 of the bra-ke valve device 3, causing the pressure within the chamber 31 to correspond to that supplied to the relay valve piston chamber 91.

As the pressure within the piston chamber 31 increases, the upward force on the self-lapping piston 35 acts against the downward force of the spring 38 to move the piston 36 and its stem 35 upwardly, causing the iloating lever I5 to iulcrum about its rounded end I4 to move the connecting link and the pivot pin I8 upwardly. As the pivot pin I8 moves upwardly, the spring 32 causes the contact carrying lever I9 to fulcrum about its right hand end, thus separating contact members 2| and 24 prior to the separation of the contact member 22 from the contact members 26 and 29. Upon separation of the contact member 2| from the contact member 24, the circuit through the winding of the magnet 10| is interrupted and the spring |08 urges the application valve |02 to its seat, cutting off the further ow of iluid to the piston chamber 91 of the relay valve device and to the self-lapping piston chamber 31 of the brake valve device. Fluid under pressure supplied to the relay piston chamber 91, causes the application piston |03 and its stem |09 to be moved upwardly, so that the slide valve III is moved upwardly to lap the ports II4 and II5, thus closing communication from the slide Valve chamber ||2 to the atmospheric exhaust passage II6. The upward movement of the piston also operates to close oi communication from the chamber |33 to the atmosphere through exhaust port |35. The degree of pressure within the piston chamber 91 and the self-lapping piston chamber 31 will depend upon the degree of movement of the brake valve handle I2 from its release position. If the brake valve handle is moved further from its release position, the -cam I3 will again operate the lever I5 to close the circuit to the application magnet valve device `through contact members 2| and 24, and this will cause a further increase in fluid pressure in the relay piston chamber and in the selflapping piston chamber 31. The relay valve will,

therefore, operate to effect a further supply of fluid under pressure to the brake cylinder I.

The stem |09 in its upward movement engages first the pilot valve stem |23 and then the hollow supply valve stem |25). Engagement of the piston stem I|l9 with the pilot Valve stem |29 raises the pilot valve |21 fromr its seat in the valve stem |20 to open communication from the pilot valve chamber |22 to the relay slide valve chamber ||2. Fluid under pressure will pass from the pilot chamber |22 into the slide valve chamber I|2, past the pilot valve I2I at a much more rapid rate ,than it can be supplied from the supply valve chamber |23 to the pilot valve chamber through the restricted port |22, thus rapidly decreasing the pressure within the pilot valve chamber. Consequently when the piston stem Ille engages the hollow stem |22 of the supply valve I I'I, the fluid pressure on the upper side of the supply valve is substantially reduced and the supply valve is then subject mainly to the force of the spring I2|, urging it against its ring seat ISI. The supply valve II'I is, therefore, raised from its seat more quickly because of Athe prior venting of the chamber |22, permitting the supply of fluid under pressure from the volume reservoir lili:` to the brake cylinder I through pipe and passage |25, supply valve chamber |23, past the supply valve II'I to the slide valve chamber |I2 and through passage and pipe II3.

Movement of the supply valve IH from its seatto effect the supply of fluid under pressure to the slide valve chamber II2 and to the brake cylinder i, also effects the supply of fluid under pressure through the restricted port |34 to the chamber |33, causing the pressure within the chamber |33 to build up to the pressure within the slide Valve chamber II2, but at a slightly slower rate. When the pressure within the chamber |33 becomes substantially equal to that within the piston chamber 9T, thus equalizing the 4pressure on the upper and lower sides of the application piston Idil, the supply valve spring |2| will force the supply valve Ii'i and the piston stem Iii@ downwardly, causing the supply Valve to seat and cut oir" communication from the volume reservoir |26 to the brake cylinder I, excepting for the small amount of now that takesplace through the restricted port |24 and past the pilot valve |2I. Should the stem |09 not immediately move sufiiciently to permit the pilot valve ll to seat, the gradual supply of uid under pressure from the supply valve chamber |23, through the restricted passage |24, the pilot valve chamber |22, past the unseated pilot valve I2? to the slide valve chamber il?, and through the restricted port |34, to the chamber |33, will cause the pressure on the upper side of the application piston I ila to build up suiiiciently to move the application piston and the stem |519 sufficiently to effect disengagement between the end of the piston stein |ilil and the end of the pilot valve stern |26, thus permitting the pilot `valve to be forced to its seat by the pressure of the spring |23. Should the pressure within the slide valve chamber il? and the brake cylinder become greater than that within the relay piston chamber Si, either as the result of an increase in pressure within the slide valve chamcer lill, or a decrease in pressure within the piston chamber lil, the application piston w8 and the stem |29 will move downwardly surficiently to cause the slide valve Ill to slightly open the ports H4 and II5, permitting the flow a pressure substantially corresponding to the pressure within the relay piston chamber 97.

In a similar manner movement of the brake valve handle I2 from a position within its electric application zone, to or toward its releasev position, effects a corresponding movement of the cam I3 and a lowering of the fulcrum point formed by engagement of the cam with the rounded end iii of the floating lever I5. This It will, therecauses the lever l5 to pivot about the pin 34.I

to move its right end, together with the Contact" carrying lever I9, upwardly to effect separation of the contact members 22 and 29 and deenergization of the winding of the release magnet valve device, and movement of the release mag-A net valve 89 to its upper or fluid releasing posi tion to effect the release of fluid under pressure from the self-lapping piston chamber 3l and the relay piston chamber 91, and an operation of the relay valve device to effect a corresponding release of fluid under pressure from the brake" cylinder I.

If the vehicle is moving in such direction as to carry the retardation control device 6 toward the left, as viewed in Fig. l, and if, while thelv brakes are applied, the rate of retardation of the vehicle becomes suiiicient to cause the pendulum 49 to swing toward the left and actuate the spring pressed plunger |54 against the stop member 68, the switch contact member 5I will be forced out of engagement with the switch;

contact member 52, interrupting the circuit to the magnet EBI of the application magnet valve device 81, and preventing further operation of the application valve |02 to a brake applying y position. In this position of the retardation controllei1 pendulum, the application and release magnet valves I2 and 39, respectively, Will be maintained in their lap positions. If the rate of retardation of the vehicle becomes suicient to cause the pendulum i9 to swing further toward the left, so as to move the spring pressed plunger 64 and the stop 68, carrying the sleeve 69, against the pressure of the spring 13, the

switch member 5d will be forced out of engagement with the switch member 55, thus interrupting the circuit through the conductor 63 and the winding of the release magnet valve device 8B, and effecting operation of the release magnet valve 89 to its fluid releasing position. effects a release oi luid under pressure from the brake cylinder I, in the manner above described, until the rate of retardation of the vehicle has become suflicient to cause the pendulum Q9 to swing toward the right a sufficient amount to permit the switch contact member 54 to again engage the contact member |55 and complete the circuit through the conductor 63 and the winding of the release magnet valve device 86, to again effect movement of the valve 89 to its lap position.

If the brakes are applied while the vehicle is traveling in a direction to carry the retardation controller 6 toward the right, as viewed in Fig. l, the inertia of the pendulum i9 will cause it to swing against the pressure of the spring This V pressed plunger 65, and, if the rate of retardation becomes sufficient, to cause operation of the spring pressed switch contact members 51 and 6I, in the same manner as the spring pressed contact members 5| and 54 were actuated upon movement of the pendulum 49 toward the left, to interrupt the circuit through the conductors 59 and 63, respectively.

Should the electric circuits to the application magnet valve device 81, and the release magnet valve 86, fail for any reason, the operator may effect a pneumatic application of the brakes by movement of the brake valve handle I2 beyond lts electric application zone to its pneumatic service application, or to its emergency application position, as defined by the notched plate I0 shown in Fig. 4. As will be apparent by reference to Figs. 3 and 4, the rotary valve 4| is in a release zone and the triple valves which control the pneumatic application of the brakes, are in their release positions for any position of the brake valve lever I2 within the electric application zone, and the pneumatic lap position, pneumatic service application position, and pneumatic emergency application position of the lever I2 and rotary valve 4I are beyond the electric application zone.

If the operator desires to effect a pneumatic service application of the brakes, he moves the brake valve handle I2 to its pneumatic service application position, in which position fluid under pressure is vented from the brake pipe 'l to the exhaust port 46, through cavity 41 in the rotary valve 4|. The reduction in brake pipe pressure thus produced, causes the piston |43 and the piston stem |44 to be moved upwardly, first moving the graduating valve |46 to lap the port |55 in the slide valve |45, and to effect communication, through a port |83, between the slide valve chamber |01 and a passage |84, Within the slide valve |45, which passage terminates in upper and lower ports and |86, respectively, in the valve seat, and then moving the slide valve |45. As the piston stem |44 continues its upward movement, a finger |81 at its lower end engages the lower shoulder of the slide valve |45, moving the slide valve to its service application position to lap the end of the passages |54, 94, and 92 in the valve seat, and to effect registration of the valve ports |85 and |86, respectively, with the passages |60 and |48, effecting communication from the auxiliary reservoir |06, and the slide valve chamber |01, to the brake cylinder volume reservoir |41 and to the relay valve piston chamber 91, the latter communication being effected through the passage |60, the inshot cut-01T valve chamber |62, and the passage 95 to effect an operation of the relay valve device to apply the brakes in accordance with the pressure within the relay piston chamber 91, 4as explained above when describing the electric application of the brakes. When the pressure within the relay valve piston chamber builds up to the value at which the inshot cut-off valve operates, the piston |65 will be forced downwardly, permitting the ball valve |63 to seat and prevent further iiow of uid under pressure to the relay valve piston chamber.

If the operator moves the brake valve handle I2 to its pneumatic emergency application posi-y tion, Ilud under pressure will be vented from the triple valve piston chamber I4 I, and the brake pipe 1, at a more rapid rate, causing the piston |43 and the slide valve |45 to be moved upwardly until the port |88 registers with the end of the passage |60 in the valve seat to effect communication from the slide valve chamber |01 to the relay piston chamber 91 through the inshot cutoii valve chamber |62 in the same manner as when a pneumatic service application of the brakes is made, and to move the lower end of the slide valve |45 upwardly sufficiently to unlap the end of the passage |48 leading to the brake cylinder volume reservoir |41, to effect communication from the auxiliary reservoir |06 and the slide valve chamber |01 to the brake cylinder volume reservoir |41.

As explained, the inshot cut-olf valve device |6| is eiective, upon either pneumatic service application of the brakes or pneumatic emergency application of the brakes, to limit the degree of braking pressure effected through operation of the triple valve. This is desirable upon pneumatic application of the brakes after failure of the electric circuits, because the retardation controller is not then effective to reduce the degree of braking pressure in case of too great a rate of deceleration of the vehicle, as is the case when the brakes are applied electrically. A greater initial degree of application of the brakes is, therefore, permitted when an electric application is made. Upon movement of the brake valve handle I2 to pneumatic service or emergency position when the electric control mechanism is functioning properly, the triple valve effects a rapid supply of fluid under pressure to the relay valve device until a pressure is reached sufficient to cause the inshot valve to close. At the same time liuid under pressure is being supplied to the relay valve device past the electrically operated application valve |02.

The safety valve device |69 is effective to limit the pressure within the relay valve piston chamber 91 when the release magnet valve device 86 is deenergized and the release valve 89 is unseat'- ed, thus effecting communication from the piston chamber 91 to the atmosphere through the passage 96, restricted port 95, chamber 90, valve chamber 9|, passage 92 and safety valve device |69. 'I'he safety valve |69 retains fluid under pressure within the relay piston chamber when the pressure has been reduced to some predetermined value.

Should the operator move the brake valve handle I2 to its pneumatic service application position or to its pneumatic emergency application position while the electric circuits are operative, thus making a combined electric and pneumatic application of the brakes, and should the electric self-lapping brake valve device operate to interrupt the circuit through the winding of the release magnet valve device 8E and permit the release valve 89 to be moved from its seat while the triple valve is in either its service or its emergency position, in which position communication from the release valve chamber 9| to the atmosphere through the exhaust passage 94 is closed, iiuid under pressure will be released from the relay valve piston chamber 91 through the release valve chamber 9| and the safety valve device IS, until the pressure has been reduced to that pressure at which the safety valve closes. A predetermined pressure will, therefore, be retained within the relay valve piston chamber until the triple valve is moved to its release position.

While I have illustrated and described one preferred embodiment of my invention, it will be apparent to those skilled in the art that many modifications thereof may be made within the spirit of my invention, and I do not wish to be limited otherwise than by the scope of the appended claims.

Having now described my invention, what I claim` as new and desire to secure by Letters Patent, is:

1. In a fluid pressure brake for vehicles, the combination with a brake cylinder, of valve means operative to open communication through which uid under pressure is supplied to the brake cylinder, and valve means operative to open communication through which fluid under pressure is released from the brake cylinder, electrically operable means for controlling said valve means to effect the application and release of the brakes, manual means for controlling the operation of said electrically operable means, pressure responsive means for controlling the operation of said electrically operable means in accordance with the degree of application of the brakes, and inertia controlled means having contact members connected in circuit between said manually operable means and said electrically operable means for interrupting the energization of said electrically operable means.

2. In an electropneumatic brake, the combination with a brake cylinder, of electrically controlled means for effecting the supply of iiuid under pressure to the brake cylinder, a self-lapping mechanism, including a chamber, for controlling the electric circuit of said electrically controlled means and operative upon an increase in fluid pressure in said chamber for causing said electrically controlled means to cut off the supply of iiuid under pressure to the brake cylinder, and an inertia controlled means for interrupting the circuit to said electrically controlled means upon a predetermined rate of retardation of the vehicle,

3. In a iluid pressure brake, the combination with a brake cylinder, of electrically controlled means for effecting the supply of fluid under pressure to the brake cylinder and to a chamber manually operable contact making means therefor having a self-lapping mechanism, including said chamber, operative upon an increase in fluid pressure in said chamber for effecting the cutting on of the supply of fluid under pressure to the brake cylinder, an inertia controlled contact making means for effecting the deenergization of said electrically controlled means independently of the operation of said manually operable control means to limit the rate of retardation of the vehicle. e

4. In a uid pressure brake, the combination with a brake cylinder, of electrically controlled` means for eifecting the supply of uid under pressure to the brake cylinder and to a chamber, manually operable control means therefor having a self-lapping mechanism, including said chamber, operative to close an electric circuit for eiiecting the supply of uid under pressure to the brake cylinder and to said chamber, and operative upon an increase in uid pressure in said chamber for electing the cutting off of the supply of fluid under pressure to the brake cylinder,

and an inertia controlled means having a switch in circuit between said manually operable control means and said electrically controlled means operative for interrupting the control circuit therebetween upon a predetermined rate of retardation of the vehicle.

5. In an electropneumatic brake, the combination with a brake cylinder, of electrically controlled means operative when energized for effooting the supply of fluid under pressure to the brake cylinder, a self-lapping mechanism, including a chamber, for controlling the electric circuit of said electrically controlled means and operative upon an increase in fluid pressure in said chamber for causing said electrically controlled means to cut off the supply of fluid under pressure to the brake cylinder, and an inertia controlled means having a switch in circuit with said electrically controlled means operative for interrupting the control circuit upon a predetermined rate of retardation of the vehicle.

6. In an electrop-neumatic brake, the combination with a brake cylinder, of electrically controlled means comprising magnet valve devices operative when energized for eifecting the supply of fluid under pressure to the brake cylinder and operative when deenergized for effecting the release of fluid under pressure from the brake cylinder, a self-lapping mechanism, including a chamber, for controlling the electric circuit of said magnet valve devices and operative upon an increase in fluid pressure in Said chamber for causing an operation of said magnet valve devices to cut off the supply of fluid under pressure to the brake cylinder, and an inertia controlled device for interrupting the circuit to said magnet valve devices upon a predetermined rate of retardation of the vehicle.

'7. In an electrically controlled brake for vehicles, in combination, electrically operable means effective when energized for applying the brakes and when deenergized for releasing the brakes, manually operable means for controlling said electrically operable means, pressure responsive means for controlling the operation of said electrically operable means in accordance with the degree of application of the brakes and inertia responsive means effective upon a predetermined rate of deceleration of the vehicle for interrupting the circuit to said electrically operable means independently of the, operation of said manually operable means.

8. In an electrically controlled bra-ke for vehicles, in combination, electrically operable means for controlling the application and release of the brakes, manually operable means including electric contact members for controlling said electrically operable means, pressure responsive means subject to brake cylinder pressure for also operating said contact members to control the operation or" said electrically operable means in accordance with the degree of application of the brakes, and an inertia responsive device having switch contact members through which the circuits controlled by said rst. named Contact members are completed for controlling said electrically operable means in accordance with the rate of deceleration of the vehicle.

9. In an electrically controlled brake for vehicles, in combination, electrically operable means for controlling application and release of the brakes, manually operable means for controlling said, electrically operable means, pressure responsive means for controlling the operation of said electrically operable means in accordance with the degree of application of the brakes, and an inertia controlled device operable to interrupt a circuit between said manu-ally operable means and said electrically operable means upon a predetermined rate of retardation of the vehicle.

10. In a brake equipment for vehicles, the combination with a brake cylinder, of a control valve device having a magnet valve section, a triple valve section, and a relay valve section, said relay Valve section controlling the supply of fluid under pressure to, and the release of fluid under pressure from, said br-ake cylinder, said magnet valve section and said triple valve section being effective to control the operation of said relay valve section, manually operable means having switch contact members for controlling said magnet valve section and valve means for controlling triple valve section in accordance with a desired degree of braking, and an inertia responsive device having switch contact members for also controlling said magnet valve section in accordance with the rate of retardation of the vehicle.

11. In a brake equipment for vehicles, the combination with a brake cylinder, of a control valve device having a magnet valve section, a triple valve section, an inshot valve section, and a relay valve section, said relay valve section being effective to control the supply of fluid under pressure and the release of iluid under pressure from said brake cylinder', said magnet valve section, inshot valve section, and triple valve section being effective to control the operation of said relay valve section, manually operable means for controlling said m-agnet valve section and said triple valve section in accordance with a desired degree of braking, and speed controlled means for also controlling said magnet valve section.

12. In a brake equipment for vehicles, braking means, electroresponsive control means for controlling the application and release of the brakes, pneumatic control means for controlling the application and release of the brakes, a retardation controller for governing said electroresponsive control means to limit the degree of application of the brakes in response to the rate oi deceleration of the vehicle, and valve means for limiting the degree of application of the brakes to a predetermined amount when applied in response to the operation of the said pneumatic control means only.

13. In a brakeequipment for vehicles, braking means, electroresponsive control means and pneumatic control means. for controlling the application and release of said braking means, valve means for limiting the degree of application of the brakes upon operation of said pneumatic control means to a brake applying position to a lesser amount than that permitted upon operation of said electroresponsive control means to a brake applying position, and retardation controlled means for decreasing the degree of application or the brakes when applied through operation of said electroresponsive control means.

14. In a brake equipment for vehicles, a brake cylinder, electrical means and pneumatic means for controlling the supply of fluid under pressure to said brake cylinder, manually operable means for eifecting the operation of said control means, valve means for limiting the brake cylinder pressure to a predetermined amount upon operation of said pneumatic means to a brake applying position, and a retardation controller for limiting the brake cylinder pressure upon operation of said electrical means to a brake applying position.

15. In a brake equipment for vehicles, a brake cylinder, a relay valve for controlling the supply of fluid under pressure to and the release of fluid under pressure from said brake cylinder, magnet valve means for controlling the supply of fluid under pressure to and the release of uid under pressure from said relay valve, a triple valve for controlling the supply of fluid under pressure to and from said relay valve, manually operable means for controlling said triple valve and said magnet valve means, an inshot valve for limiting the supply of iluid under pressure supplied through operation of said triple valve to a brake applying position to a value less than permitted upon operation of said magnet valve means to a brake applying position, and retardation controlled means for governing said magnet valve means for limiting the degree of application of the brakes in response to the rate of retardation of the vehicle.

l5. In a brake equipment for vehicles, a brake cylinder, magnet valve means for controlling the supply of iluid under pressure to said brake cylinder, a triple valve for controlling the supply of fluid under pressure to said brake cylinder, manually operable means for controlling the operation of said magnet valve means and of said triple valve, an inshot valve between said triple valve and said brake cylinder for limiting the supply of fluid under pressure to said brake cylinder upon operation of said triple valve to a brake applying position and retardation controlled means for governing said magnet valve means to limit the degree of application of the brakes in response to the rate of retardation of the vehicle.

1'7. In a brake equipment for vehicles, a brake cylinder, magnet valve means for controlling the supply of fluid under pressure to said brake cylinder, a triple valve for controlling the supply of fluid under pressure to said brake cylinder, manually operable means for controlling the operation of said magnet valve means and of said triple valve, an inshot valve between said triple valve and said brake cylinder for limiting the supply of fluid under pressure to said brake cylinder upon operation of said triple valve to a brake applying position, retardation controlled means for governing said magnet valve means to limit the degree of application of the brakes in response to the rate of retardation of the vehicle, and means permitting a partial release only of fluid under pressure from said brake cylinder upon operation of said magnet valve means to its release position while said triple valve is in other than its release position.

18. In a brake equipment for vehicles, a brake cylinder, magnet valve means for controlling the supply of fluid under pressure to said brake cylinder, a triple valve for controlling the supply of fluid under pressure to said brake cylinder, manually operable means for controlling the operation of said magnet valve means and of said triple valve, and valve means for limiting the supply of fluid under pressure to said brake cylinder upon operation of said triple valve to a brake applying position, and means permitting a partial release only of fluid under pressure from said brake cylinder upon operation of said magnet valve means to its release position while said triple valve is in other than its release position.

19. In a brake equipment for vehicles, a brake cylinder, magnet valve means for controlling the supply of fluid under pressure to said brake cylinder, a triple valve for controlling the supply of fluid under pressure to said brake cylinder, manually operable means for controlling the operation of said magnet valve means and of said triple valve, and means permitting a partial release only of fluid under pressure from said brake cylinder upon operation of said magnet valve means to its release position while said triple valve is in other than its release position.

20. In an electropneumatic brake, in combination, a brake cylinder, electrically controlled valve means for controlling the supply of fluid under pressure to the brake cylinder, means for controlling said valve means comprising manu ally operable means having contact members for controlling the circuit of said electrically controlled means, means on said manually operable means for also operating said Contact members to control said circuit according to the degree of iiuid pressure supplied to the brake cylinder, and inertia controlled means having contact members in series circuit relation with said above named contact members for also controlling said circuit.

21. In a brake equipment for vehicles, magnet Valve means for controlling the supply of fluid under pressure for effecting application and release of the brakes, fluid pressure responsive valve means `normally subject to fluid under pressure and operative to an application position Vupon a reduction in fluid pressure to supply fluid under pressure for eiecting application of the brakes, means for controlling said magnet Valve means, means for eiecting a, reduction in uid pressure to cause said fluid pressure responsive valve means to move to application position, and means rendered effective to limit the reduction in brake applying pressure effected by said magnet valve means to a certain minimum pressure only when said pressure responsive Valve means is in application position.

ELLIS E. I-IEWITT. 

